I'm sure there is a difference when the sunroof is deployed. I know on my 991, the spoiler further raises to compensate when I have the glass roof open. There are some additional aero features on the 992, this is a cool video from Porsche on 992 aero:


However I don't see why when the roof is retracted there is a difference in down force, just by fact of having the option. When the sunroof is deployed, absolutely. But like in the 991, the spoiler should compensates for it by further raising. But net net, I'm sure aero is better with everything tucked in.

 

I always thought that if you had a sunroof the spoiler came up more....maybe he mixed it up, or perhaps I am wrong.

 

I thought the same...

 

Nice video. Enjoyed it and thanks for sharing!

 

With the 991.1 the rear spoiler would be a little more vertical if you opened the sunroof. I liked that if you just cracked open the rear of the roof you could hear the exhaust a little better.

 

I went to their web site where they show the times relative to other cars they have tested. The 992 C2S did quite well.

https://www.proracerstake.com

 

...and still enjoying it!

 

that's a 1 second difference between the 992s and the GT4...

that is surprising